Effects of Keystone XL Pipeline Leak into Carrizo

TABLE OF CONTENTS
1.
2.
3.
4.
5.
6.
7.
Introduction…………………………..…..…………………………………………...2
Keystone XL Pipeline Project………………………………………………………...2
Tar Sands Crude Oil………………..…….…………………………………………...3
Water Resources along Proposed Pipeline Route….…………………………………3
Potential Impacts from Leaks into Groundwater Resources………………………….6
Conclusion…………………………………………………………………………….9
References……………………………………………………………………………11
EXHIBITS
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Proposed Pipeline Route Across the U.S.
Proposed Pipeline Route Across the State of Texas
Proposed Pipeline Route Across Major Surface Waters of Texas
Proposed Pipeline Route Across the Major Aquifers of Texas
Typical Cross-Section of Carrizo-Wilcox Aquifer
Location of 3 Carrizo-Wilcox GAMs
Proposed Pipeline Route Across the Carrizo-Wilcox Aquifer within GMA #11
Proposed Pipeline Route Across the Regional Planning Areas
Proposed Pipeline Route Across the Groundwater Conservation Districts
Proposed Pipeline Route Across the Major River Basins
Proposed Pipeline Route Across various Faults in Northeastern Texas
Various Fault Zones in Northeastern Texas
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EFFECTS OF KEYSTONE XL PIPELINE LEAK INTO CARRIZO-WILCOX AQUIFER
by: Lawrence G. Dunbar, P.E.
March 2011
1. Introduction
The purpose of this report is to identify potential impacts of a leak or spill from the
proposed Keystone XL Pipeline that is to be located in eastern Texas on the groundwater
resources in the area. Of greatest concern is the potential impact on the Carrizo-Wilcox aquifer
in northeastern Texas where portions of the pipeline will cross over the outcrop of this aquifer,
where near-surface water is in direct communication with the remainder of the aquifer. This
aquifer is one of the three largest and most significant aquifers in Texas, and is a major source of
drinking water. A major oil spill from this proposed pipeline project could have disastrous
impacts on the human and natural resources in the area.
Information in this report has primarily come from the Draft Environmental Impact
Statement for the Keystone XL Pipeline Project and documents available from the Texas Water
Development Board website.
2. Keystone XL Pipeline Project
The Keystone XL Pipeline project is part of a proposed pipeline project for transporting
hazardous liquid material (e.g. tar sands crude oil) from Canada to the Gulf Coast in southeastern
Texas. The proposed route of this pipeline across the United States is shown on the enclosed
Exhibit 1. A more close-up view of this pipeline project as it is proposed to cross eastern Texas
is shown on Exhibit 2.
The Draft Environmental Impact Statement (DEIS) for this project describes this pipeline
project as follows (Section ES.2):
“The Project would consist of approximately 1,380 miles of new 36-inchdiameter pipeline in the U.S. The proposed pipeline would cross the international
border between Saskatchewan, Canada and the United States near Morgan,
Montana. The Project initially would have the nominal transport capacity of
700,000 barrels per day (bpd) of crude oil, with up to 200,000 bpd delivered to an
existing terminal in Cushing, Oklahoma and the remaining amount shipped to
existing delivery points in Nederland (near Port Arthur), Texas, and Moore
Junction (in Harris County), Texas. By increasing the pumping capacity in the
future, the Project could ultimately transport up to 900,000 bpd of crude oil
through the proposed pipeline. At that throughput, up to 200,000 bpd would be
3
delivered to the Cushing Oil Terminal and the remainder would be delivered to
the existing terminals in Texas.”
The following table, from the DEIS, lists the miles of new pipeline by state for the proposed
Keystone XL Project:
According to the DEIS, the 36-inch-diameter pipeline will be buried underground with at
least 4 feet of cover (Table 2.3.2-2), with the existing, natural soil at the location of the pipeline
to generally be used for covering after excavation and placement of the pipeline in the ground
(Section 2.3.2.5). Thus, any leak from the pipeline would release the transported liquid material
directly into the existing soils surrounding the pipeline and the adjacent environment. Of
particular concern for this report is the potential for release of the transported hazardous liquid
material into the nearby water resources in Texas along the proposed pipeline route, especially
the Carrizo-Wilcox Aquifer in northeastern Texas.
3. Tar Sands Crude Oil
The primary material to be transported through this proposed Keystone pipeline into
Texas from Canada is tar sands crude oil, known as bitumen. Bitumen is one of the most
complex molecules found in nature. According to the Canadian Encyclopedia, “Bitumen is the
heaviest, thickest form of petroleum… unlike conventional crude oil, bitumen does not flow
freely; it is heavier than water and more viscous than molasses… To deliver bitumen, it must
first be diluted with natural gas condensate or similar material to make it pumpable.”
Of particular concern for this report is the potential for release of this hazardous liquid
material into the nearby water resources in Texas along the proposed pipeline route, especially
the Carrizo-Wilcox Aquifer in northeastern Texas, and how it might affect this valuable water
resource. The Government of Alberta, Canada acknowledges on its website that the release of
bitumen into water can result in the bitumen-derived hydrocarbon compounds going into
solution (the Athabasca River has always had measurable levels of oil sands-derived
hydrocarbon compounds, including Polycyclic Aromatic Hydrocarbons, because of bitumen
seeping into the river from exposed oil sands along the river banks). Sufficient release of
bitumen into a water resource therefore can result in rendering the water resource not useable for
drinking water.
4. Water Resources along Proposed Pipeline Route
This proposed Keystone XL pipeline will be crossing numerous surface water features
throughout eastern Texas, as shown on Exhibit 3. In addition, this pipeline will cross over
various groundwater resources, as shown on Exhibit 4.
4
One of the largest aquifers to be potentially affected by this pipeline project in Texas is
the Carrizo-Wilcox Aquifer. A typical cross-section of this aquifer is shown on Exhibit 5. This
aquifer has been modeled by the Texas Water Development Board (TWDB) in three segments
(north, central and south) for estimating groundwater availability (see Exhibit 6). The Northern
Carrizo-Wilcox Groundwater Availability Model (GAM) covers the area of this aquifer where
TABLE ES.2.1-1 Miles of Pipeline by State for the Proposed Project
MT
Steele City Segment
Gulf Coast Segment
Houston Lateral
Project total
SD
282.5
0.0
0.0
282.5
314.1
0.0
0.0
314.1
NE
254.1
0.0
0.0
254.1
OK
0.0
155.4
0.0
155.4
TX
0.0
324.8
48.6
373.4
Total
850.7
480.2
48.6
1,379.5
the proposed pipeline project will cross. This portion of the aquifer is also part of the aquifer
system within the Groundwater Management Area #11, as shown on Exhibit 7.
The following are excerpts from the Final Report on the Northern Carrizo-Wilcox
Aquifer GAM (2003) that provide some background information about this aquifer and its
importance to this region:
“The Carrizo-Wilcox Aquifer is classified as a major aquifer in Texas (Ashworth
and Hopkins, 1995) ranking third in the state for water use (430,000 acre-feet per
year [AFY]) in 1997 behind the Gulf Coast aquifer and the Ogallala aquifer
(TWDB, 2002). The aquifer extends from the Rio Grande in South Texas to East
Texas and continues into Louisiana and Arkansas. The Carrizo-Wilcox aquifer
provides water to all or parts of 60 Texas counties with the greatest historical use
being in and around the Tyler, Lufkin-Nacogdoches, and Bryan-College Station
metropolitan centers and in the Wintergarden region of South Texas (Ashworth
and Hopkins, 1995).
The model area includes portions of the North East Texas Region (Region D) and
the East Texas Region (Region I) (Figure 2.4), and all or parts of the following
Groundwater Conservation Districts (Figure 2.5): (1) the Anderson County
Underground Water Conservation District, (2) the Brazos Valley Groundwater
Conservation District (3) the Neches and Trinity Valleys Groundwater
Conservation District, (4) the Piney Woods Groundwater Conservation District,
(5) the Bluebonnet Groundwater Conservation District, (6) the Lone Star
Groundwater Conservation District, (7) the Mid-East Texas Groundwater
Conservation District, and (8) the Lake Country Groundwater Conservation
District.
The East Texas Regional Water Planning Group (Region I) plans to meet 59% of
their projected water needs by the year 2050 through the use of existing
groundwater supplies. The North East Texas Regional Water Planning Group
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(Region D) plans to meet 25% of their 2050 projected water needs through
existing groundwater supplies and an additional 2% through new groundwater
resources.
The model area intersects five major river basins from west to east: (1) the
Brazos, (2) the Trinity, (3) the Neches, (4) the Sabine, and (5) the Red River
basins (Figure 2.6). In the model area, the Red River Basin has been further
subdivided into the Sulphur River Basin, the Cyprus Creek Basin, and the Red
River Basin. The model domain also intersects the San Jacinto River Basin, but
only in the downdip portion of the model where there is no direct interaction
between streams and the model. Eight river authorities (Angelina-Neches River
Authority, Brazos River Authority, the Lower Neches Valley Authority, the Red
River Authority, the Sabine River Authority, the San Jacinto River Authority, the
Sulphur River Basin Authority, and the Trinity River Authority) are present in the
model area.
The aquifer is recharged with water from rainfall or from streams infiltrating the
outcrop. The Northern region of the aquifer receives the majority of its water
from the Brazos, Trinity, Neches, Sabine, and Red River basins. The drainage
area of these river basins is nearly 115,000 square miles, and there are 48 major
reservoirs. These rivers are perennial and gain flow from the underlying
geology…”
The above-referenced Figures 2.4, 2.5 and 2.6 are shown herein as Exhibits 8, 9 and 10. Exhibit
10 shows that the proposed pipeline route would cross the Neches River, the Sabine River and
the Cyprus Creek as the pipeline passes over the Carrizo-Wilcox Aquifer.
Additional excerpts are provided from a report on the Carrizo-Wilcox Aquifer in Texas by Scott
Jones (2008) as follows:
“The Carrizo Sand, composed of homogenous fluvial sands, unconformably
overlies the more heterogeneous Wilcox Group. The northeastern part of this
portion of the aquifer is known as the Cypress Aquifer due to the lack of
confining units between aquifers (Fryer et al., 2003)…
Groundwater in the aquifer exists under both water-table and artesian conditions.
Water-table conditions usually occur in the outcrop areas, and artesian conditions
occur where the aquifer is overlain by confining beds with lower hydraulic
conductivity rates. Well yields are usually 500 gal/min, but some may reach 3,000
gal/min downdip where the aquifer is under artesian conditions (Thorkildsen and
Price, 1991).
6
The groundwater pumped from the Carrizo-Wilcox aquifer is used primarily for
municipal public water supply, rural domestic use, and manufacturing in
approximately 60 counties in Texas. Approximately 35 percent of the total
groundwater removed from the aquifer is for municipal water supply; the largest
public water supplies, Bryan-College Station, Lufkin-Nacogdoches, and Tyler,
make up a large portion of that percentage as they receive all of their water from
the Carrizo-Wilcox aquifer. These major municipalities include over 370,000
people, but the aquifer as a whole provides water to ten to twelve million people
(National Wildlife Federation et al, 2006). The Southern region of the aquifer is
usually pumped heavily for irrigation purposes, but irrigation pumping occurs
throughout the aquifer accounting for nearly 51 percent of the total groundwater
removed…
The groundwater of the Carrizo-Wilcox Aquifer in Texas is one of the greatest
assests of the East-Central region of Texas. It provides water for agriculture,
industry, and human consumption and use.”
As discussed above, the Carrizo-Wilcox Aquifer is a valuable water resource for East Texas, and
as such, it must be protected from becoming contaminated from tar sands crude oil leaking out of
an overlying pipeline. Not only would the groundwater in the aquifer become contaminated, but
the surface waters in the area that are fed by this aquifer could also become contaminated.
5. Potential Impacts from Leaks into Groundwater Resources
If there were to be a leak or spill from this proposed pipeline in Texas, the potential for
impacting the groundwater resources in the area of the release could be substantial, depending on
a number of factors, including the spatial and temporal extent of the release, and exactly where
the release takes place (especially if it occurs in the outcrop of the aquifer).
The DEIS acknowledges the potential impacts to groundwater quality resulting from a
spill or leak associated with construction activities for this project, especially where the aquifer
is near the surface, as is the case with the outcrop area of the Carrizo-Wilcox Aquifer. According
to the Draft EIS for the Keystone XL Pipeline Project (Section ES.6.3.1):
“Potential impacts to groundwater during construction activities could include:
groundwater quality degradation during or after construction resulting from
disposal of materials and equipment, or vehicle spills and leaks; … degradation
of groundwater quality due to potential blasting; and groundwater withdrawal for
hydrostatic testing… Many of the aquifers present in the subsurface beneath the
proposed route are isolated by the presence of glacial till or other confining units,
which characteristically inhibits downward migration of water and contaminants
7
into these aquifers. However, shallow or near-surface aquifers are also present
beneath the proposed route and may be impacted by construction activities.”
Of greater concern is a potential spill or leak during operation of the pipeline as it is transporting
the hazardous tar sands crude oil. Section ES.6.13.1 of the DEIS discusses the potential risk of
such an oil spill, as follows:
“Releases of crude oil from the Project and appurtenant facilities could occur.
Spill frequency can be estimated using historic spill frequencies on other
pipelines… Releases of oil or petroleum products would affect the environment
to varying degrees, and would be of concern to all stakeholders… Spills from the
proposed pipeline, associated pump stations, valves, or pigging facilities could
occur during Project operation and have the potential to result in larger-volume
spills… Although leak detection systems would be in place, some leaks might not
be detected by the system.”
Potential impacts to groundwater from an oil spill are discussed in Section 3.13.4 from the DEIS,
and includes the following statements:
“Substantial spills of refined products, especially diesel, and substantial to very
large spills of crude oil may reach groundwater where the overlying soils are
porous and not water saturated, and the water table is relatively near the surface.
Areas near major wetlands and meandering streams or rivers are key examples
where the water table may be close to the surface and the soils are wet to
saturated, depending on rainfall and snowmelt conditions. In some of these areas,
it may be difficult to distinguish between groundwater and surface water.”
Furthermore, the DEIS notes in Table 3.13.4-2 that there would be a “substantial” impact to the
groundwater if there were a large to very large spill from this pipeline.
The outcrop area of the Carrizo-Wilcox Aquifer, as the primary source of recharge for this
aquifer (TWDB 2003), provides overlying soils that would be most susceptible to allowing a
release of hazardous tar sands crude oil to enter into and contaminate the groundwater of this
aquifer system.
The DEIS continues with the following statements:
“Diesel fuel or gasoline has a low viscosity and likely would percolate toward the
water table, where it would float on the water. It may move downgradient with
the groundwater, although potentially at a lower rate than the groundwater. Some
of the diesel may become dispersed in the groundwater, contaminating the
groundwater for agricultural or domestic drinking supply uses. Some of the diesel
8
may become adsorbed or adhere to soil grains and remain there for years as it
very slowly weathers or degrades. The oil-contaminated groundwater may
contaminate surface waters (e.g., wetlands, ponds and lakes, streams and rivers)
if the groundwater surfaces and discharges into these surface water areas.
Crude oil is more viscous than refined products and would percolate downward
more slowly. Furthermore, a substantial portion of the crude oil may adhere to
the soil particles, thereby reducing the amount that reaches groundwater. Once
crude oil reaches the groundwater surface, most of it would float and may move
downgradient with the groundwater, although probably more slowly. The oil also
would undergo some biodegradation, adsorption to soil particles, and dispersion
into water, causing a natural attenuation and remediation of the contamination.
Like diesel fuel, crude oil may reduce or eliminate agricultural or domestic use
of the groundwater and may contaminate surface waterbodies if the
contaminated groundwater discharges into these waters. (emphasis added).
During the life of the Project, potential minor short to long-term groundwater
quality degradation is possible from equipment and vehicle spills or leaks.
Routine operation and maintenance is not expected to affect groundwater
resources; however, if a crude oil release occurred, crude oil could migrate into
subsurface aquifers and into areas where these aquifers are used for water
supplies.” (emphasis added).
The DEIS acknowledges that the hazardous tar sands crude oil could migrate into a subsurface
aquifer (like the Carrizo-Wilcox Aquifer), may reduce or eliminate agricultural or domestic use
of this groundwater, and may contaminate surface water resources if the contaminated
groundwater discharges into these waters. The major rivers in this area are recognized as being
perennial and gain flow from the underlying geology, such as the Carrizo-Wilcox Aquifer
(TWDB 2003). Thus, a release of this tar sands crude oil into the water resources in the area
could have disastrous results. And with this crude oil being heavier than water, having an API
gravity of 7.7-9, (NRDC, 2010) the cleaning up of such an oil spill and removal of the
contamination from the water resources in the area would be extremely difficult.
The DEIS concludes with the following:
“In summary… the low probability of large, catastrophic spill events and the
routing of the proposed pipeline to avoid most sensitive areas suggest a low
probability of impacts to human and natural resources. Nevertheless, the potential
for construction and operation-related spills does exist.” (p. ES-20)
9
The DEIS states that while the potential for spills would still exist with the transporting
of the tar sands crude oil, it also notes that the routing of the proposed pipeline was done to avoid
most sensitive areas in order to conclude that there was a low probability of impacts to natural
resources.
However, the routing of this pipeline is directly across numerous faults in
southwestern Rusk County, as shown on Exhibit 11 herein, obtained from the DEIS. If these
faults are “active”, then there is an increased risk of pipeline failures/ruptures as the ground
shifts, with subsequent releases of the hazardous tar sands oil into the surrounding soils and nearsurface waters. With the outcrop area of the Carrizo-Wilcox Aquifer being located in the vicinity
of where the pipeline would cross this fault zone (see Exhibit 7), it is important to know for sure
that these faults are not “active”.
The DEIS states that “the proposed route would not cross any known active
faults…” (Section ES.6.1.4). Furthermore, the DEIS notes in Section 3.1.4.1 that “in Texas,
surface faults have been mapped in the project area. There is little evidence of ground
movement along these faults, and as such, they pose very minimal risk to the pipeline” (Crone
and Wheeler 2000). Review of the report by Crone and Wheeler (USGS Open-File Report
00-260) dated 2000 revealed that this report is only a preliminary report and was simply a
systematic evaluation of published information on 69 features in Central and Eastern U.S. for
classification purposes and to compile a national database regarding potentially significant
earthquake areas. The report even states that “it is very likely that the inventory presented in this
report is incomplete.” This USGS report that was cited by the DEIS as the source of the
information used to conclude that these faults “pose very minimal risk to the pipeline” is not a
reliable source for determining whether there are active faults along the proposed pipeline route
in Texas. This USGS report was not intended to be a complete compilation of active faults in
Central and Eastern U.S., rather it was intended to be an initial start to a compilation of potential
areas for significant earthquakes, a source of reference material for seismicity. As such, it should
not have been used to conclude that the faults in southwestern Rusk County are not “active” and
therefore would not pose any risk to the proposed pipeline.
In fact, there is documentation evidencing that this area does contain active faults. For
example, a Bureau of Economic Geology report (Geologic Circular 84-3) by Pennington and
Carlson dated 1984 states that several recent earthquakes “occurred near the Mount Enterprise
Fault System along a 90-km segment and may represent activity along that fault system, along
nearby secondary faults, or both.” The Mount Enterprise Fault System is shown on Exhibit 12
and includes the faults in southwestern Rusk County where the proposed pipeline will be
located. Furthermore, an October 2010 DEIS from the Corps of Engineers regarding a proposal
for a lignite mining project in Rusk County states:
“Northeast Texas is not a seismically active area (USGS 2009b). A search of the
USGS earthquake database found two earthquakes events within 60 miles of the
study area from 1973 to the present (National Earthquake Information Center
2009). Historically, strong earthquakes have been felt in the area. In 1891, there
was a strong earthquake in the vicinity of Rusk, Texas, approximately 60 miles
10
southwest of the study area. Reports indicated that the intensity of the earthquake
may have been equivalent to a 5.0 to 5.9 magnitude earthquake (USGS 2009c).
This earthquake is thought to have originated from the Mount Enterprise Fault
Zone (Davis et al. 1989). There is some evidence of historical movement on the
fault zone, which would indicate that it is active (Ferguson 1984). The cause of
the movement is not certain; however, it may be related to movement of the
Louann Salt that comprises the “basement” of the East Texas Basin.”
This information about fault activity in the Mount Enterprise Fault Zone raises serious questions
about the potential for an increased risk of failure of the proposed pipeline that is to be routed
through this fault zone area in the immediate vicinity of the outcrop area of the Carrizo-Wilcox
Aquifer.
6. Conclusion
Contrary to the above claims made in the DEIS suggesting a low probability of impacts
to human and natural resources, the route of the proposed pipeline does not avoid the most
sensitive areas when it comes to the Carrizo-Wilcox aquifer, since the pipeline will cross the
outcrop portions of the aquifer, where a near-surface oil spill of tar sands crude oil would be able
to enter into the aquifer system, degrading its water quality. In addition, the fact that the
proposed route of this pipeline will be directly through the Mount Enterprise Fault Zone will
only increase the probability of a spill.
The DEIS acknowledges that the spilling of the hazardous tar sands crude oil could
migrate into a subsurface aquifer (like the Carrizo-Wilcox Aquifer), may reduce or eliminate
agricultural or domestic use of this groundwater, and may contaminate surface water resources if
the contaminated groundwater discharges into these waters. The major rivers in this area are
recognized as being perennial and gain flow from the underlying geology, such as the CarrizoWilcox Aquifer. Thus, a release of this tar sands crude oil into the water resources in the area
could have disastrous results. And with this crude oil being heavier than water, the cleaning up
of such an oil spill and removal of the contamination from the water resources in the area would
be extremely difficult.
Thus, special precautions need to be taken to minimize the likelihood that any of this
hazardous liquid material could escape and enter into the water resources in the area in the event
of a spill. The consequences of such a spill migrating into the groundwater and/or surface water
are significant enough to necessitate a design that can assure the users of these water resources
that their source of water is not at risk of being contaminated by tar sands crude oil.
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7. REFERENCES
1. USGS Open-File Report 00-260, Crone and Wheeler. (2000).
2. Draft Environmental Impact Statement for the Proposed Keystone XL Pipeline Project.
3. Final Report on the Northern Carrizo-Wilcox Aquifer GAM Texas Water Development Board
(2003).
4. Natural Resources Defense Council, Tar Sands Pipeline Safety Backgrounder, Dec. 2010.
5. Jones, Scott. (2008). Carrizo-Wilcox Aquifer in Texas.
6. Geologic Circular 84-3, Bureau of Economic Geology report, Pennington and Carlson. (1984).
7. DEIS for the Rusk Lignite Mining Project, USACE-SWF, Oct. 2010.
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EXHIBIT 1: Proposed Pipeline Route across the
United States (from DEIS for Keystone XL Project)
13
EXHIBIT 2: Proposed Pipeline Route across the State of
Texas (from DEIS for Keystone XL Project)
14
EXHIBIT 3: Proposed Pipeline Route across the Major
Surface Waters of Texas (from TWDB)
15
EXHIBIT 4: Proposed Pipeline Route across the Major
Aquifers of Texas (from the TWDB)
16
EXHIBIT 5: Typical Cross-Section of the Carrizo-Wilcox
Aquifer (from TWDB)
17
EXHIBIT 6: Location of 3 Carrizo-Wilcox GAMs (from
TWDB)
18
EXHIBIT 7: Proposed Pipeline Route across the CarrizoWilcox Aquifer Within GMA#11 (from the TWDB)
19
EXHIBIT 8: Proposed Pipeline Route across the Regional
Planning Areas (from the TWDB)
20
EXHIBIT 9: Proposed Pipeline Route across the
Groundwater Conservation Districts (from the TWDB)
21
EXHIBIT 10: Proposed Pipeline Route across the Major
River Basins (from the TWDB)
22
23
EXHIBIT 11: Proposed Pipeline Route across various
Faults In Northeastern Texas (from DEIS for Keystone
XL Project)
24
EXHIBIT 12: Various Fault Zones In Northeastern Texas
(from TWDB)
25